Automatic telephone system.



F. RQUAYLE. AuToMATlc TELEPHONBSYSTEM. APPLICATION FILED JAN-5. i914.

mw, N Q, w um m 44., ,m

u L 5. 4. A E YW COMPANY, OF CHICAGO,

AiIToMA'rIc TELEPHONE SYSTEM.

Specification of Letters 15atent.

Application filed' January 5, 1914'. serial no. $110,440.

To all tf1/2,0m t may concern.'

Be it known that I, FREDERICK R. QUAYLE, a citizen of the United States of America, and resident of llVilmette, Cook county, Illinois, have invented Improvements in Automatic rTelephone Systems, of which the following is a specification'.

My invention relates automatic telephone systems, and more particularly to an improved non-numerical trunk-selecting switch for use in said systems. Heretofore, non-numeric`al trunk; selecting switches have been provided which are enabled to automatically select an' idle trunk from among` a group .of trunks; object of my invention is, however, vide a non-numerical trunk-selecting which is enabled to first automatically select a group of trunks, and then tof automatically select an idle trunk in that group. In this manner the non-numerical switch is en'- abled to have access to a much larger num; ber of trunk lines, and the operationv is furthermore' expedited owing to the fact that the first movement of the switch first automatically selects aA smaller `group in which there is an idle trunk, and the next movement automatically selects an idle trunk in this group. v

rhese and other kfeatures of my invention will be more readily understood by reference to the accompanying drawings, in which. l have illustrated one embodiment of my invention in connecti on with a portion of an automatic telephone system, showing the manner in which this non-numerical switch is enabled to select an `idle trunk line eX- tending from a subscribers line to a selector switch.

ln the drawing Figure yl represents diagrammatically a portion ofl the central oifi'c'e apparatus necessary for completing aV connection between a calling' subscriber and a called subscriber. u y

Fig. 2 is a detail view showing a portion of the private bank contacts and the private wiper for making contact with said bank contacts.

Fig. 3 is a sectional `view lineu 3)*3 in Fig. 2. p p

Fig". l is al detail view of a portion of the non-numerical selector private" bank contacts. f U

Referring to Fig". l, the syst-'ern as therein to improvements in taken on the certain new and 'usefulv -purpose of completing a may be similar represented, consists of the substation A the conductorof which. terminates in an individual non-numerical selector switch E which has accessto a group of'selector yswitches F. The trunk lines leading i lector switch F may terminate in any suit'- able type of automatic yapparatus for the connection. The completing the connection n to thatv disclosed patent to T. lMartin No. V14199 of 1910.

The s'ubscriberfsl .substation A is of any suitable or approved type and usualreceiver 2,transmitter ringer 5 and condenser 6. i it is als'oprovided with an impulse trans# mitter'or calling device, which is represented herein by a pair of impulse springs 7 and Sand an impulse wheel 9, which latter is assumed to be controlled through the me'- i diiun of a linger hole dial V(not shown) in such a'. manner that lthe impiilse springs 7 and 8 may be' momentarily separatedl a number of times corresponding to the digit called. v

VThe first selector switch eral type of selector switch disclosed` in United States Letters Patent No. 48l5,32l, granted March 13,1906, tovKeith, Erickson' and Erickson', except that the ssc-called side switch is omitted and the circuits are modified to adapt thefswitch to operate in a syster'n in which it is controlled by impulses delivered over two sides of the line linI series. Among other details', the selector switch comprises banks of contacts arranged in horizontal rows A or levels which are adapted to be engaged by a set ofwipers l0, ll and l2 carried upon a shaft (not shown) which has a I controlled by the vertical magnet" `13 yand a rotary movement controlled by the rotary magnet. 14. The operations of lthe various parts of the switch are controlled through the medium of the double-woiind line relay l5. Means for permitting the switch to be restored to normal `position are provided in the release magnet 16, which, upon energizing, withdraws the vretaining pawls from theshaft;y The springs Hand 18 close only when the'switch shaft has' beeny raised one or more steps from its lowest posi-` tion. The rrelays 19 and 20 are slow acting; that is, relays which denergizeslowly after their energizing circuits are apparatus for F' is of the genfrom thesaid seemg an automatic substation vertical movement atented Oct. 253-, 19t t. `Y

rlhe non-numerical selector E for extend ing a connection from the subscribers line A to the selector F is similar in construction to the selector switch F, the circuits being modiiied, however. Among other details, the non-numerical selector E comprises a bank ot' line contacts (not shown) arranged in horizontal rows or levels, which contacts are adapted to be engaged by a set ot line wipers 21 and 2,2 carried upon a shaft (not shown) which has a vertical movement controlled by the vertical magnet :23 and a rotary movement controlled by the rotary magnet 2a. The vertical. movement ot' the switch, instead ot being controlled through the medium ot the calling subscriber`s substation impulse transmitter, as isl the case with the selector F, is automatic and is controlled through the medium of the wiper 26 and the auxiliary bank contacts 2'?, as will be hereinafter described. There is also a bank ot private contacts arrangedl in rows or levels, a portion or' which is shown in Fig. 4i This bank ot contacts consists of ten groups r levels, similar to the line banks, each group comprising ten pairs of contacts. rThe private wiper Q5 is provided with a pair of wiping arms 30 and 3l. rl`he wiping arm 3l is adapted to make contact with any one or the upper contacts on any level, while the wiper 30 is arranged to make contact between the corresponding lower bank contact and the adjacent lower contact to the lett. The end pair of contacts ot each level are connected together by means of a short circuiting strip 32. A plurality ot these selectors E are arranged in a group and have access to the same group or trunks, and the corresponding contacts in the bank ot private contacts ot each selector are multipled together, in the usual manner. lllhenever the ten contacts of any certain level are all busy, there will be a wiper similar to the wiper 30 spanning the tirst and second contacts ot one of these multiple private banks, another wiper spanning the second and third contacts, and so on, until we have a circuit passing from the tlrst to the last contact, and as the last pair ot contacts of said level are connected together, a guarding potential will be placed on the auxiliary bank contact 2.7 cor responding to said certain level. This circuit extends from ground through the wiper arm 3l or' the switch resting on the tenth contact of lsaid level, through the short-circuiting strip 39. and thence over the Vcircuit through the lower row or contacts and the spanning wiper 30 to the auxiliary bank contact 27. The extra bank contacts 27 ot the different levels form an auxiliary bank of contacts, as shown in Fig. 4:. To the private fiper 25 is attached an extra wiper 2.6 arranged to wipe over the auxiliary bank con-- tact 27,` thereby controlling the vertical. mo-

tion of the switch. rlhe extra wiper 26 is shorter than the wipers 30 and 31, so that when the shaft is rotating, the said wiper QIC will be carried in front ofthe levels ot the said bank. Means 'for permitting the switch to be returned to normal position are pro vided in the usual release magnet 'lhe springs 3d and 35 close only when the switch Vshaft has been raised one or more steps from its lowest position. rlhe relays 3S, 37 and are slow acting relays. The slow acting relay 33 is so arranged that it may operate its interruptor springs 39 without the slow acting relay denergizing.

Having given a general description of the apparatus involved in the system, in order to give a complete understanding or' my invention, I will now describe the operation of the selector .E when the calling subscriber er, upon removing his receiver, causes this non-numerical selector E to select an idle selector switch l?. lt will be assumed that all the trunk lines ot the first two levels are busy, thus placing a guarding ground potential'on the bank contacts 27 corresponding to thek first two rows or levels of bank contacts. Upon the removal of the receiver from the switch-hook at the substation A preparatory to making a call, an energizing circuit is closed from ground G1 throughthe lower winding of the line relay 40, springs el and l2 of the switching relay 43, line conductor all, through the subscriberls substation A, over the return line conductor 45, springs lo and 4:7 and the upper winding of the relay Ll() to battery B, thence through battery B to ground G. The relay e0, upon energizing, closes a circuit through the relay 37 extending from ground G2 through the contact of springs 49 and 50 and the relay 37 to the battery B. The relay 37, upon energizing, supplies a guarding ground potential to the connector private bank contacts 87 to prevent the calling line being seized by a connector switch. This circuit extends from ground through the contact ot' springs 5l and over the conductor 53 to said private bank contact. When the switch is in normal position, the wiper 26 contacts with the lowerinost contact ot' the bank 2T, which contact is connected to ground G4. Therefore, the energization ot the. rela'7 3'? also closes a circuit through the vertical magnet 23, said circuit extending rom ground GL vthrough the wiper 26, contact of springs2, relay 36, vertical magnet 93, interruptor springs 39 and the relay 38 to battery B, thus energizing the vertical magnet 23 and the relays 36 and 38. rlhe vertical magnet 23 operates to raise the switch shaft and wipers one step to a position opposite the irst row or level of contacts. rlhe' relay 38, upon energizing, opens the above-traced circuit at the interrupter springs 39, thus denergizing the vertical magnet 23 and allowing the armature of said vertical magnet to return to normal y circuit for itself extending position. The relay 38, however, denergiz'es and Yagain `closes the above-'traced circuit at the interrupter springs 39 before the relay 36 has had time to denergize. I t having been assumed that ,all the trunks of the ii-rst level are busy, and therefore the vbank contact 27 connected to the first level of pri vate bank contacts connected to ground, the wiper 26, upon engaging' his grounded bank contact 27, again closes a circuit through the vertical magnet 23 and the relay 38 to battery B, thus causing the vertical magnet to operate to. raise its shaft and wipers another step, i. c., opposite the second row or level of bank contacts. The above operation will continue until the switch shaft and Wipers are raised to a position opposite a row or level of bank contacts that contains one or more idle trunk lines, which, in this instance, has been assumed to be the third level As above stated, the relay 36 remains energized as long as impulses are being sent through the vertical magnet, and, in its energized condition, this relay closes a circuit from ground G5 through the contact of springs 54 and and the relay 57 to battery B. The relay 57, upon energizing', closes a locking from ground G3 through the springs 5l, rotary magnet springs 58 and 59, oif-normal springs 35, springs 6l and 62 of the relay 57, thence through the relay 57 to battery B. Itl will be observed that the locking circuit for the relay 57 passes through the o-normal springs 35 and these off-normal springs are, of course, not closed until the switch shaft is raised at least one step. The relay 57 controls in part the circuit of the rotary magnet 24 and is locked in its energized position at this time for the purpose ofpre (paring the 4circuit over which the rotary magnet 2a is subsequently to be operated. Thus, upon the denergization or' the relay 36 after the vertical shaft has raised its wipers opposite a level that contains one or more idle trunk lines, the circuit of the rotary magnet is closed.- This circuit extends from ground G3 through the contact of springs 5l, springs 58 and 59, olf-normal springs springs 61 and 62, springs 55 and 56, interrupter springs and the rotary magnet 24C to battery B. The rotary magnet, upon energizing, rotates the wipers one step, and, by opening the springs 58 and 59, disconnectsY ground G3 from itself and the relay 57. If the rst trunk line of the second level is idle, the relay 57 denergizes as soon as the springs 59 and 58 are opened. lf this trunk lin-e is busy, however, the wiper arm 3l of the private wiper 25 linds the' contact with which it engages provided with a guarding ground potentialv whichV istransmitted to the relay through the springs 6l and 62, thereby preventing it from denergizing.- The rotary magnet, however, de-` energizes when the springs (S0 disengage, regardless of. whether the relay 57 remains energized, and the circuit oil the rotary magnet will be again closed as soon as the` armature drops back far enough to close the springs 58 and 59. The rotary magnet will, therefore, operate in a manner similar to that of a buzzer to advance the wipers step by step? over the contacts. until the non-` grounded contact oi" the idle trunl-c line is reached by the wiper 25, whereupon. the relay denerg'izes. The relay 57, upon deenergizing, whether after one or several operations vof the rotary magnet, perni'anentlybreaks the circuit of the 1nagnet'2-l` and closes the circuit of the switching relay 43. The circuit through the said relay extends r'rom ground w3 through the Contact or' springs 5l,- springs 58 and 59, orf-normal springs 35, springs 61 and 63 and the relay 43 to battery B. The relay 48, upon ener` gizing, dis-connecte the line relay 40 from the line and extends thelin-e connection over the heavy conductorsshown through Vthe wipers 2l and 22 to the selector switch F.

When the connection is completed to the selector Ftl1e circuit of the line relay-l5 is closed. rlhe relay l5,- upon energizing', closes an energizing circuit through the slowrelay 20. The relay 20, upon energizing, supplies a new holding ground to the relay 4.3 of the non-numerical selector E, the original circuit having been broken by the denergizatioi'i of ythe relay 37 oi' the non-numerical selector E. The said circuit extends fromv ground- GG through the contact of springs G4, wiper arm 31 of the wiper 25, springs 6l and 63 and't'herelay 43 to battery B. rilhe energiza# tion of the relay 20 also prepares a circuit for the vertical magnet 13 and opens the circuit 'of the release magnet 16.

The apparatus is now in condition to receive impulses corresponding to the firstv digit of the called number. The calling' subscriber therefore operates his calling device, which causes impulses to be transmitted through the lineV relay of the selector F, which selector then operates in the wellknown manner to extend connection to the trunk line 82`84. As any suitable type of selector switch can be employed in con#v nection with my invention, and as Vthe parL ticular selector employed forms no part of my invention, it is not thought necessary to describe its operation in detail. The connection to' the called line can then'be completed either through other automatic switches or through a manual board, in a` manner well understood in the art. After the conversationis completed, the release of the apparatus is brought. about by hang'- ingup thexreceiver'at the calling substation inthe usuall manner. In .the system here shown the usual form of trunk-release is employede-that is, the apparatus at the suggest themselves to those called end ot' the connection is iirst released and the release of this apparatus destroys the holding circuit for the switching relays @t3 and 85 of the non-numerical selector E and the selector F. rlhe relay 85 of the selector E, upon denergizing, closes a circuit through the release magnet 16 of said switch, thus causing the releasev of this switch in a well-known manner. rlhe relay a3 of the non-numerical selector E, upon deenergizing, closes a circuit through the release magnet 33. |This circuit extends trom ground 2 through the springs i9 and d8, springs 90, springs 3e and the release magnet 38 to battery B The non-numerical switch E then releases in a well-lrnown manner common to selector switches of this type and breaks the circuit ot its own release magnet when the shatt reahes its lowest osition.

lt will thus be seen that l have devised a very ellicient non-numerical selector switch which may have access to a large number ont trunk lines without having to pass over the individual contacts of each busy trunk before engaging the contacts ot an idle trunkthat is, by my invention l have provided a non-numerical trunk-selecting switch which, by one movement, can first select a comparatively small group in which an idle trunk is located, and then, by a second movement, can select an idle trunk in that group.

Vhile l have illustrated one particular embodiment of my invention and have shown the same as extending connection to a selector switch of a well-lrnown type, it will, ot course, be understood that my invention is not in any way limited to the particular use to which this non-numerical selector switch is various changes and modiiications in the non-numerical selector switch will readily skilled in the art and come wihin the contemplated scope of my invention. For example, the contacts yin one level of one non-numerical switch may be slipped to connect with the corresponding contacts in a different level of another non-numerical switch in the same group, and so on, thereby avoiding the objection or" having all the iirst levels ot all the switches become busy before the second level.

"What l claim as my invention is 1. ln a telephone system, a plurality of trunk lines divided into groups and each terminating in an automatic selector switch, a subscribers line provided with an individual line switch having access to said trunk lines, means responsive to the removal of the receiver on said line for operating said individual switch to iirst select a group Uopies of this patent may be obtained for five cent placed. Furthermore,

s each, by addressing the oli trunk lines containingl an idle trunk and then select an vidle trunk in the selected group, whereby said subscribei"s line is ci@ tended to an idle selector switch, and means responsive to the replacement of the receiver on said line for restoring the said individual switch to normal position. 2., ln a telephone system, a plurality of trunk lines divided into groups and each ter minating in an automatic selector switch, a subscribers line provided with an individual line switch having access to said trunk lines, 7 5 means responsive to the removal ot the lreceiver on said line tor operating said individual switch to iirst select a group of trunk lines containing an idletrunk and then select idle trunk in the selected group, whereby said subscribers line is extended to'an-idle selector switch, a holding circuit 'lior preventing the release oi' said individual switch, and a relay in said selectortswitch energized over the extended subscribers line torontrol the 85 continuity of said holding circuit', whereby the release or said line switch may be con# trclled over said subscricers line. f

3. ln a telephone system, a pluralityot subscribers lines, each provided with an in-Y dividual switch, a plurality of `groups oi trunk lines accessible tosaid switches in common, means in each switch responsive'to the initiation ot a call on the associated line 'tor selecting Va group of trunl lines containingA an idle trunk and tor then selecting an idle trunk line in the selected group, multipletest contacts in said switches corresponding to groups of trunk lines and wipers coperat; ing therewith to control the group selection, and means in a plurality oi' switches coperating to place a busy potential on one of said test contacts. l

4l. ln a telephone system, a plurality oi' subscribers lines each provided with an individual switch, a plurality of groups 'ot trunk lines accessible to said switches in common, means in each switch responsive 'to the initiation of a call on the associated line for selecting a group of trunk lines containing an idle trunk and for then selecting an idle trunk? line in the selected group, multiple test contacts in said switches corresponding to groups of trunk lines and wipers cooperatingv therewith to control the group selection, a circuit tor the multiple test contacts of each` group for placing a busy potential thereon, and means in a plurality ot switches coperating to complete one ot' said circuits. I

Signed by me at Chicago, illinois, this 27th 12( day of December, 1913.

FRED. lt. QUAYLE.

Witnesses:

'RAYMOND ll. BUnrniND, T. E. Marcin f Commissioner of Patents' Y Washington, D. C. 

